Hand trucks of the general character described herein are frequently used by delivery persons, movers, and the like, to transport loads from place to place. Typically, such trucks comprise a rigid elongated frame, a pair of handles, and a pair of wheels whose axle is rigidly mounted to the base of the frame. Positioned adjacent the wheels is a load bearing platform upon which the goods or other objects to be moved are placed.
Although providing a simple means of transporting loads, conventional hand trucks of this type present several disadvantages. First, these hand trucks are difficult to use in small spaces. For instance, when a particular load can only be approached alongside a wall, removal of the load is complicated by the wall since it will typically prohibit turning of the truck. In such cases, the truck and the load being carried thereon must be slowly moved away from the wall along a path nearly parallel with the wall.
Even where there is adequate space with which to operate the truck, conventional trucks present an increased opportunity for on-the-job injury. When the truck is under load, especially under heavy loads, and the operator wishes to make a sharp turn with the truck, the operator must swing the handles to the side of his or her body. If the operator does not concurrently shift his or her body along with the handles, the operator is left supporting the weight of the load on one side of the body. This results in awkward twisting of the torso which places excessive strain on the muscles of the middle and lower back.
In addition to being difficult to use in cramped quarters and creating unnecessary strain on the operator, standard hand trucks are cumbersome and difficult to maneuver. Even when operated correctly in open spaces, wide sweeping turns are needed to manipulate the load and carry it to the intended destination.
Several attempts have been made to remedy the difficulties conventional hand trucks present. For example, U.S. Pat. No. 2,235,043, issued to Renning, discloses a steerable hand truck which can be turned with pivoting handles. Although seemingly adequate in operation, the steering mechanism of the hand truck extends towards the operator in a position likely to interfere with the operator's feet while walking behind the truck. In U.S. Pat. No. 2,800,336, Major et al., disclose a hand truck having a wheel direction shifting mechanism which permits the operator to change the alignment of the wheels. This mechanism cannot be changed during hauling, however, and requires the operator to bend over and shift the wheels manually with a lever when a change in alignment is desired.
From the above, it can be appreciated that there is a need for a steerable hand truck that is easily maneuverable by the operator so that hauling of loads is simplified to the greatest extent possible and the possibility of operator injury is minimized.